As per GLX_EXT_swap_control, the GLX swap interval is specified on a
per-drawable basis. However, QGLXContext only tracks it per-context
using the m_swapInterval member. If a new drawable is made current to a
context, it is still necessary to call glXSwapIntervalEXT to change the
swap interval, even if it has been previously called for the same
context with a different drawable. However, currently,
QGLXContext::makeCurrent doesn't do this if its m_swapInterval field
matches the new swap interval. This change removes m_swapInterval from
QGLXContext, instead tracking it in QXcbWindow. This still avoids
unnecessary calls to glXSwapIntervalEXT, while ensuring the swap
interval is always set for new window drawables.
Change-Id: Idc34101476c6af618059f6f3d8925dee743994a3
Reviewed-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
Reviewed-by: Laszlo Agocs <laszlo.agocs@qt.io>
0c18311785